Touch-screen image scrolling system and method

ABSTRACT

Electronic image displays, of lists that extend beyond the vertical display dimension of the display screen, are displaced in the vertical direction by touching the screen with a finger and then moving the finger in the desired direction on the screen. In a natural manner, the initial speed of displacement of the displayed image corresponds to the speed of motion of the finger along the screen. When the user&#39;s finger is disengaged from the screen, the system senses the disengagement and thereafter allows the vertical displacement speed of the image to decrease at a controlled rate. When it is desired to stop the motion of the image at a given point, or to make a selection from the displayed image, the system measures the length of time that the finger is in contact with the screen and the distance that the finger is moved during that time, to determine if a selection is desired or if it is desired only to stop displacement of the image. That is, a short term contact with the screen, say 500 ms or less, accompanied by little or no displacement on the screen, can be identified as an intended selection, while a longer contact with little or no accompanying displacement can be interpreted as being intended to stop the motion of the image without making a selection.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to displays of information data in theform of sequential lines of symbols commonly comprising lists of wordsand numbers, and more specifically relates to the use and control ofelectronic forms of such displays.

2. Description of the Related Art

It has become well-known to display lists of words and numbers onelectronic display screens for ready access by users. Often, such listsextend in length beyond the dimensions of the electronic screen, and insuch cases it has further become well-known to cause the image of thelist to “scroll” past the screen so that a line of text comprisingwords, numbers or other symbols, appears to travel from one edge of thescreen to the other until a desired section of the list, or portion of aline, appears on the screen.

It is known that the systems and methods currently being used to controlthe scrolling motion of the screen image are subject to numerouslimitations and disadvantages. For example, in one system a cursor maybe positioned at one edge of the screen and then moved toward theopposite edge while holding down a selected “mouse” button, therebyengaging and “dragging” the screen image in a desired direction. It iswell known that such displacement of the screen image is slow andcumbersome except for relatively slight relative movements. Anothersystem in current use activates an automatic continuous “scrolling”motion of the image when the cursor is positioned on a specific portionof the image, while a selected mouse button is depressed. This requiresholding down the selected button until the desired portion of the screenimage is displayed. A related system in current use varies the speed ofthe scrolling motion in accordance with the position of the cursorrelative to the edge of the screen. All of these cursorposition-responsive control systems are subject to similar limitationsof screen clutter, lack of aesthetic visual appeal, and the requirementfor manipulation and handling of the mouse device.

SUMMARY OF THE INVENTION

The invention herein disclosed improves upon the scroll-like display ofdata on electronic display screens by making it possible for auser/viewer to access a desired portion of a long list of data andinformation by scrolling to the location of that portion rapidly and ina more natural manner than heretofore possible.

The present invention overcomes and avoids the limitations of knowncontrol systems for scrolling electronic displays by providing atouch-screen responsive system that imparts a scrolling motion to thedisplayed image in response to the motion of a finger in contact withthe screen. The speed and direction of motion of the finger along thescreen determines the initial speed and direction of motion for theimage. After the finger separates from the screen, the image continuesto move in the same direction at a gradually decreasing speed untilmotion is stopped manually by touching the screen without movement ofthe finger, or the speed decreases to zero, or to a predeterminedminimum speed, or until the image reaches its “end”. Alternatively,continued motion of the image may be achieved or again increased byrepeating the “sweeping motion” of a the user's finger along the screen.Motion of the displayed image may be stopped manually by applying afinger to the screen without moving it along the surface of the screenfor a finite period of time. If a finger is applied to the surface ofthe screen for a shorter period of time, for example for a period lessthan a minimum set time, the finger touch can be deemed to be a“selection” of an item or “thing” corresponding to the image displayedat the touched location. Still further, if the finger touch on thescreen is made to move with the display, but at a slower rate than thethen-current rate of movement, the display will be slowed to a ratecorresponding to the motion of the finger at the movement that contactis broken.

This operation of the system of this invention is achieved byprogramming a microprocessor-based control system to displace the imageon a screen display, such as the screen of a conventional cathode raytube, in response to a finger touch on the screen and the direction of afinger motion along the surface of the screen at the initial speed ofthe finger motion. Thereafter, the speed of displacement is caused todecay at a selected rate (units of displacement per unit of time, or afunction thereof), until the displacement finally stops (for example,due to having reached the end of the “scroll”) or until it is stoppeddeliberately as explained herein.

In accordance with this invention, the scrolling motion of data on thedisplay screen moves in a seemingly “natural” way, moving initially at aspeed imparted by the motion of the user's finger, with the speedthereafter slowing at a constant rate until it ultimately comes to rest,unless it is terminated earlier.

Moreover, if the speed of scrolling is found to be slow at a pointdeemed to be too far before the desired location in the scroll, thescrolling speed may be increased as many times as possible by merelytouching the screen again to impart “new” motion to the display.

At any desired point or time while a scrolling motion is in progress, itmay be stopped entirely, again in a seemingly “natural” way, by merelytouching one's finger to the screen while holding it substantiallystationary for a predetermined period of time. The reason for requiringa predetermined time-period for stationary [i.e. no-motion] touch timeis to assure that the timing mechanisms will have sufficient time todistinguish between a touch intended to stop the scrolling motion and atouch [shorter in time] intended to “select” or “mark” a particular itemthat is included in the scrolled data. “Touch marking” is a well-knownfeature of scrolled display technology at this time, but this inventiondiscloses its use in combination with a new, and heretofore unknown,form of scrolling motion control.

These and other features and advantages of this invention will be mademore apparent to those having skill in this art, by reference to thefollowing specification considered in conjunction with the accompanyingdrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow-chart representing the sequential operations of atouch-screen image scrolling system in accordance with this invention.

FIG. 2 is simplified pictorial representation of a touch-screen imagescrolling system in accordance with one embodiment of the invention ofFIG. 1.

FIG. 3 is a simplified block diagram of another embodiment of atouch-screen image scrolling system in accordance with FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following description, certain specific details of the disclosedembodiment such as architecture, interfaces and techniques, etc, are setforth for purposes of explanation rather than limitation, so as toprovide a clear and thorough understanding of the present invention.However, it should be understood readily by those skilled in this art,that the present invention may be practiced in other embodiments whichdo not conform exactly to the details set forth herein, withoutdeparting significantly from the spirit and scope of this disclosure.Further, in this context, and for the purposes of brevity and clarity,detailed descriptions of well-known apparatus, circuits and methodologyhave been omitted so as to avoid unnecessary detail and possibleconfusion.

Referring now to the block diagram of FIG. 1 of the drawings, the methodof operating a touch-screen image scrolling system 10 (as shown inFIG. 1) in accordance with this invention may be seen to begin in step100 with sensing the touch of a finger upon an electronic display screen100 a having a stationary data display, determining the period of timethat the finger is in contact with the screen 100 b, and determining ifthe finger moves or remains stationary 100 c. The technology andmethodology for sensing and determining the appropriate values forinformation of the type herein disclosed is well-known to persons havingskill in this art, and is not further described or discussed in thisspecification.

If no motion occurs and the touch contact continues for less than apredetermined minimum time, the touch is treated in step 100 as a“selection” of the data term touched, and the system continues with“selection” path 102. The operation of a selection path, beginning with,for example, highlighting of the term or icon touched, is well-known andis of no further concern in connection with the operation of the systemof this invention. However, if the touch contact continues for more thanthe first predetermined minimum time, and the finger then moves afterthat time, the process of the invention will proceed to step 103, inwhich the “selected” item on the list will then “stick to the finger” sothat the item can be repositioned on the list by the known process of“touch-dragging”. This repositioning step can be very desirable tofrequent users who may wish to cluster several preferred items in agiven location. After an item has been repositioned in step 103, andfinger contact with the screen is interrupted, the process will revertto “waiting” status. With advance reference to step 105, explainedbelow, it should be noted here, that in this step it is a selected item,rather than the entire display, that “sticks to the finger.”

In another feature, if no motion of the finger occurs while the screenis stationary, and the contact continues for less than a second minimumtime which is less than the first minimum time by a readily measurablefinite value, then step 100 ignores the contact and the system revertsto “waiting” status, awaiting further input signals.

However, if step 100 senses motion in association with the finger touchon the screen, during the finite period between the first predeterminedtime and the second, then the method of the invention proceeds to step104, converting the speed and direction of motion of the touch intocorresponding initial scrolling motion of the displayed data. And step104 proceeds directly into step 106. Step 104 either proceeds to step106, or diverges to step 105 depending upon whether the finger isremoved from contact with the screen or continues in contact with thescreen.

That is, if the finger touch of step 104 imparts movement to the displayand the touch-contact is then broken, movement of the display continuesin accordance with step 106. However, if contact with the screen is notbroken, the method of the invention proceeds from step 104 to step 105,wherein the entire display [not just a selected item] in effect “sticksto the finger” so that the entire display can be moved up or down orback and forth, as the case may be, with the finger. If there is nofinger motion at the time that finger contact with the screen is brokenin step 105, the display will remain in the position it is in at thattime without further motion, and the system will revert again to“waiting” status. In the alternative, if finger contact in step 105 isbroken while the finger is in motion, the system of the inventionproceeds to step 106, as described below.

In step 106, the timer function associated with the system of theinvention measures time while the scrolling action continues and thesystem begins decreasing the scrolling speed at a controlled rate, fromits initial value which is determined by the speed of the finger touch,toward zero or until the speed is reduced to any desired, predeterminedminimum speed. It is assumed that most users of this system will preferthat the decrease in scrolling speed begin immediately after the startof scrolling. However, it should be recognized that the start of thedecreasing speed function can, in fact, be delayed so as to begin at anytime after the start of the scrolling motion. Incorporating afinite-time delay into the control system for utilization of this methodis a simple technique well within the knowledge of those skilled in thisart.

While the slowing scrolling motion continues, and after scrolling hasterminated entirely, the system continues waiting for further inputsignals, to control the next operation of the system. However, inaccordance with the invention, slowing of the scrolling speed continuesuntil one of three events occurs: (1) slowing decreases the speed of thescroll to zero or to any preset minimum; or (2) an “end of scroll” datasignal is received from the data source; or (3) a finger touch on thescreen indicates that the scrolling is to be terminated. Regardless ofthe status of the slowing action, the method of this invention allowsthe system to react to the next user-initiated input signal at any time,following step 106.

Step 108 shows that the method of the invention reacts to a finger touchon the screen during or after scrolling by repeating, essentially, thefunctions of step 100. That is, in step 108, the system senses the touchof a finger 100 a on the electronic display screen, determines theperiod of time 100 b that the finger is in contact with the screen, anddetermines if the finger moves or remains stationary. 100 b. If thetouch is stationary and the contact continues for less than apredetermined minimum time, the finger touch is treated in step 108 asboth (1) a “selection” of the data term touched, and (2) an instructionto terminate the scrolling motion. In this case, scrolling motionterminates and the system reverts to the “selection” path 102,previously mentioned. On the other hand, if the touch is stationary butthe contact does not continue for more than the minimum time, the methodtreats the touch as an instruction to terminate the scrolling motiononly, and there is no resulting “selection” of any data listing that mayhave been touched. When scrolling motion terminates under thesecircumstances, the method reverts to the state that exists before thebeginning of step 100, waiting for “instructions” in the form of inputsignals; i.e. awaiting either selection of a displayed item orinitiation of scrolling motion.

Once again it should be emphasized that the duration of contact for astationary finger touch on the screen serves as the distinction betweena “selection” touch and a “stop scrolling” touch. Although it has beenstated above, that a relatively long-term finger touch while scrollingmotion is taking place serves as both a “selection” and a “stop motion”signal, it will be obvious that the method could be set up easily sothat a finger touch during the scrolling process would act solely as a“stop motion” signal regardless of the length of the touch; this wouldprotect against the possibility of unintended “selections” resultingfrom inadvertently long touches that were intended only to “stop” thescrolling.

In contrast to stationary touching in step 108, if the system sensesmotion of the finger touch on the screen, the method reverts to step104, again converting the speed and direction of motion of the touchinto scrolling motion of the displayed data and restarting the scrollingprocess. As before, step 104 then proceeds directly into step 106.

In the embodiment of the system of this invention illustrated in FIG. 2,the system is shown to comprise a simple personal computer apparatushaving a display screen 10, a central processing unit 12 and a keyboard14 for inputting manual instruction to the processing unit 12. Inaccordance with convention, it will be understood that processing unit12 includes an internal electronic memory unit (not shown) ofconventional design and capabilities. Accordingly, for the purposes ofthis disclosure, the internal memory unit may be assumed to be thesource of a scrollable data display capable of appearing on displayscreen 10 which is accessible to a hand or stylus device, herestylistically represented by the outline of a hand 16.

In use, the computer is set up in well-known manner to display thescrollable data on screen 10, and a hand/finger or stylus 16 is touchedto the screen and moved down along the screen to impart an initialdownward “scrolling” motion to the data display. Software in thecomputer interactively responds to the contact with the screen to createthe desired displacement motion of the display and the internal timerfacility now inherent in such computer apparatus, in cooperation withthe programming of processing unit 12 responds to the start of motion bygradually decreasing the speed of displacement, as explained previouslyherein. When a desired point in the display is seen or approached, theuser may apply a hand or stylus 16 to the screen to terminate thescrolling motion. Because the scrolling motion does not involve anymoving parts with real or simulated mass, it is possible to stop themotion of the display instantly, without any difficulty or concern forinertial force consequences.

Accordingly, it will now be understood that the system and method ofthis invention facilitates a rapid, convenient and natural-feelingapproach to accessing a scroll-like display of data on a computerscreen.

In the embodiment represented in FIG. 3, the system of this invention isshown to comprise the essential elements of the computer apparatus ofFIG. 2 without having the configuration of a computer. That is, thebasic components of the system of this invention are here shown tocomprise a microprocessor 42 which is in turn coupled to a keyboard 44,a timer means 43 and a display screen 40. Each of these componentsfunctions in the same manner as its counterparts in the embodiment ofFIG. 2, with microprocessor 42 and the associated timer means 43together, here serving the same function as central processing unit 12in FIG. 2.

Although a preferred embodiment of the invention has been illustratedand described, those having skill in this art will recognize thatvarious other forms and embodiments now may be visualized readilywithout departing significantly from the spirit and scope of theinvention disclosed herein and set forth in the accompanying claims.

1. An improved touch-screen image scrolling system, comprising: an electronic image display screen; a microprocessor coupled to said display screen to display information thereon and to receive interactive signals therefrom; timer means associated with said microprocessor to provide timing capacity therefor; a source of scroll format data capable of display on said display screen; finger touch program instructions associated with said microprocessor for sensing the speed, direction and time duration of a finger touch contact with said display screen: scrolling motion program instructions associated with said microprocessor responsive to said duration of said finger touch contact such that, when said duration exceeds a first given preset minimum time and is accompanied by motion along the surface of said screen followed by separation of said finger touch from said screen, a scroll format display on said screen is caused to begin to scroll in said sensed direction and at said sensed initial speed; time decay program instructions associated with said microprocessor for reducing the rate of scrolling displacement on said display screen at a given rate until motion is terminated; stopping motion program instructions associated with said microprocessor for terminating scrolling displacement of the image on said screen upon first occurrence of any signal in the group of signals comprising: (a) a substantially stationary finger touch on the screen enduring for a period longer than a preset minimum time, and (b) an end-of-scroll signal received from said scroll format data source.
 2. The improved touch-screen image scrolling system of claim 1, wherein said scrolling motion program instructions further comprise instructions to move said display in correspondence with movement of the finger touch, in response to movement following a touch having a stationary duration greater than said first preset given minimum time and less than a second given preset minimum time.
 3. The improved touch-screen image scrolling system of claim 1, wherein said scrolling motion program instructions further comprise instructions to move a touch-selected item relative to the stationary display in correspondence with movement of said finger touch, in response to motion following a touch having a stationary duration greater than said second given preset minimum time.
 4. The improved touch-screen image scrolling system of claim 1, wherein said group of signals for terminating scrolling displacement of the image on said display screen further comprises (a) a signal indicating that the rate of scrolling displacement on said screen has decayed to a value below a predetermined given value.
 5. The improved touch-screen image scrolling system of claim 1, wherein said microprocessor, and said timer means together comprise a processing unit of a conventional computer.
 6. The improved touch-screen image scrolling system of claim 5, wherein said source of scroll format data capable of display on said display screen comprises part of the memory of said conventional computer.
 7. An improved touch-screen image scrolling system, comprising: an electronic image display screen; a computer apparatus coupled to said display screen to display information thereon and to receive interactive signals therefrom; timer means within said computer apparatus to provide timing capacity therefor; said computer apparatus having capacity to store scroll format data capable of display on said display screen; finger touch program instructions associated with said computer apparatus for sensing the speed, direction and time duration of a finger touch contact with said display screen; scrolling motion program instructions associated with said computer apparatus responsive to said duration of said finger touch contact such that, when said duration exceeds a preset minimum time and is accompanied by motion along the surface of said screen, a scroll format display on said screen is caused to begin to scroll in the sensed direction and at the sensed initial speed; time decay program instructions associated with said computer apparatus for reducing the rate of scrolling displacement on said display screen at a given rate until motion is terminated; stopping motion program instructions associated with said computer apparatus for terminating scrolling displacement of the image on said screen upon first occurrence of any signal in the group of signals comprising: (a) a substantially stationary finger touch on the screen enduring for a period longer than a preset minimum time, and (b) an end-of-scroll signal received from said scroll format data source.
 8. An improved touch-screen image scrolling system, comprising: an electronic image display screen; a microprocessor coupled to said display screen to display information thereon and to receive interactive signals therefrom; timer means associated with said microprocessor to provide timing capacity therefor; a source of scroll format data capable of display on said display screen; finger touch program instructions associated with said microprocessor for sensing the speed, direction and time duration of a finger touch contact with said display screen: scrolling motion program instructions associated with said microprocessor responsive to said duration of said finger touch contact such that, when said duration exceeds a first given preset minimum time, and is less than a second given preset minimum that is greater than said first minimum, and is accompanied by motion along the surface of said screen, a scroll format display on said screen is caused to begin to scroll in the sensed direction and at the sensed initial speed; said scrolling motion program instructions further comprising instructions to move a touch-selected item relative to the stationary display in correspondence with movement of the finger touch, in response to motion following a touch having a stationary duration greater than said second given preset minimum time; said scrolling motion program instructions still further comprising instructions to move said display in correspondence with movement of the finger touch, in response to motion following a touch having a stationary duration greater than said first given preset minimum time and less than said second given preset minimum time; time decay program instructions associated with said microprocessor for reducing the rate of scrolling displacement on said display screen at a given rate until motion is terminated; stopping motion program instructions associated with said microprocessor for terminating scrolling displacement of the image on said screen upon first occurrence of any signal in the group of signals comprising: (a) a substantially stationary finger touch on the screen enduring for a period longer than a preset minimum time, and (b) an end-of-scroll signal received from said scroll format data source.
 9. The improved method of controlling the scroll-like display of data on an electronic display screen, in accordance with claim 7, wherein said group of conditions to be sensed for terminating said scrolling motion further comprises: the speed of said scrolling motion on said screen slows to a value below a predetermined given value. 